\documentclass{article}
\usepackage{geometry,tikz,pgfplots}
\pgfplotsset{compat=newest}
\geometry{paperwidth=9.5cm,paperheight=7cm}
\pagestyle{empty}
\begin{document}
\begin{tikzpicture}[overlay,remember picture]
\begin{axis}[at={(current page.center)}, anchor=outer center,
              axis lines=left,
              zlabel = {Concentration en \%},
              ylabel = {$\lambda$},
              xlabel = {Temps (arb. units)}]
%\foreach \st in {10,25,...,110}
%{
\addplot3+[mesh,mark=none,samples=20,domain=0:130, y domain=0:0.3] {100 * (1 - 1/(1 + exp(-(y * (x-60)))))};
%}
\end{axis}
\end{tikzpicture}
\end{document}
